Laboratory evaluation of amenorrhoea

Modified by Dr R de Villiers (2007)Dr N Oosthuizen (2006)

Dept of Chemical Pathology - UPBlock 11

Amenorrhoea

• Primary (1º)• no menarche by 16y

• Secondary (2º)• cessation of established menstruation >3-6

months

• Trend of earlier onset of menarche – workup for amenorrhoea at 15y

2º Amenorrhoea Case 1• 32y ♀• LNM 3m ago

2º Amenorrhoea: CausesCause Clues Lab investigations Other

Pregnancy β-hCG

Hypothalamic 35% Weight ExerciseStress; illness

Clomiphene test

Ovarian Hot flashes; Surgery/ Trauma/ Inf/ InfiltrationPara-/Thyroid/ Adrenal

Estradiol, FSH+ Auto Ab

PCOS= DM of bearded women with anovulation

30% HyperandrogenismHirsutismWeightAcne

DHEAS; TestosteroneLH:FSHInsulin Resistance (QUICKY)

Sonar

Pituitary 19% LH, FSH; GnRH test

10% Drugs, Hypothyroidism

prolactin MRI

Uterine 5% History of processes that may endometrial scar (Asherman syndrome)

Progestin challengeProgestin + EE challenge

Hystero-scopy

Other 1%•Thyroid disorders Hyperthyroidism Sx TSH

Adrenal (CAH) Hirsutism ACTH test (17OH Progesterone)

•Iatrogenic Contraception

1º Amenorrhoea Case• 16y ♀• No menarche

1º Amenorrhoea: CausesCause Clues Lab investigations Other

Chromosomal •Turner Syndrome

•Gonadal dysgenesis•Mullerian dysgenesis

50%

15%

Turner phenotypeNo 2º sexual

Karyotype 45 X0 FSH46 XX N ♀ Testosterone

Sonar

No uterus

Hypothalamic 20% Weight ExerciseStress; illness

Vaginal•Transverse septum •Imperforate hymen

5% Cyclic pelvic pain

Pituitary 5% Short stature;Visual field

FSH, LH, Prolactin MRI

Adrenal (CAH) 5% Virilization 17OH Progesterone; DHEAS Testosterone; FSH

PCOS HyperandrogenismHirsutism; Weight;Acne

DHEAS; TestosteroneLH:FSHInsulin Resistance (QUICKY)

Sonar

Thyroid Hypothyroidism Sx

TSH

Androgen Insensitivity (Testicular Feminization)

46 XY ♂ Testosterone

Sonar No uterus

Hx and physical exam

Rule out pregnancy

Prolactin/TSH/LH/FSH

TSH

Hypothyroidism

Hyperthyroidism

Prolactin

Evaluate hyperprolactin

-aemia

FSH (>40)

Evaluate ovarian failure

LH/FSH /

Progestin challenge

Withdrawal menses +

Withdrawal menses -

Anovulation – E2 present

Oestrogen-

Progestin challenge

Withdrawal menses +

Withdrawal menses -

Anatomic defect

Anovulation – E2 absent

Hypothalamic/pituitary disease

Evaluate ovarian failure

Anatomic defect

Uterine US

Uterus absent

Uterus presen

t

Karyotype

XY XX

AIS (T)

Testicular

regression T

17-OH-ase deficiency

Mullerian

agenesis

Asherman Outflow

obstruction

Testosterone

Karyotype if <30y

XO, XO mosaic

XX

Premature ovarian failure

if <40y

Galactosaemia

17-OH-ase deficiency

Autoimmune disorder

Infection

Trauma/surgery

Resistant ovary

LH/FSH defects

Abbreviationsβ-hCG β-subunit of human chorionic

gonadotropinCAH Congenital Adrenal HyperplasiaDHEASDehydroepiandrosterone SulphateE2 EstradiolFSH Follicle Stimulating HormoneLH Luteinizing HormonePCOS Polycystic Ovarian Syndrome